3D Bioengineered Platform for Vascularized Bone Regeneration
Objectives: Bone homeostasis controls the function of various cell types, such as osteoblasts, nerve cells, osteoclasts, osteocytes, and endothelial cells within ECM scaffolds. Although conventional in vitro bone platforms focus on understanding the role of osteoblasts and osteoclasts, the role of the microvasculature in bone is unclear. Here, we engineer a three-dimensional (3D) vascularized bone platform, named bone-on a chip to deconvolute the dynamic contribution of two bone cell types: (i) endothelial cells (ECs) and (ii) osteoblasts (OB) with their surrounding ECM.
Methods: To test the microvessel integrity, we introduced fluorescent dextran (70 kDa Texas Red, Thermo Fisher) and the diffusive permeability coefficient (Pd) was measured. Also, the mineralization potential of OBs was tested by using Alizarin Red (AR) and Von Kossa (VK) staining to observe new bone formation under normal and disease conditions.
Results: This in-vitro blood vessel model is a microfluidic platform that is comprised of 3D cylindrical channels (diameter 160µm) embedded within collagen I matrix. Specifically, this bi-cellular biomimetic platform is composed of perfusable blood vessels surrounded by OB.
Conclusions: Overall, this 3D bicellular microphysiological models will be used as diagnostic tools for drug testing and identification of new targets involved in bone and craniofacial diseases.